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I have been hearing about the ISOCS equipment being used in D&D applications for open field work.  There has been discussion of using the data obtained as survey data and also as sample data.  Is any one familiar with this approach?  Is it becoming prevalent or am what I hearing isolated cases, and if so what is the trend from those usages?

I'm more interested in hearing of others experiences with ISOCS as a tool for doing D&D surveys in open field areas.  I am wondering about the usage of this equipment to replace meter scan and static readings.  I am attempting to verify what I have been told about the usage of the data obtained by ISOCS in lieu of taking soil samples.  Any knowledgeable  interface with this system would be appreciated.

I helped with the FSS Report for Yankee Rowe.  They used ISOCS in lieu of scanning in some survey units, they then also took soil samples.

RSCS worked closely with the NRC to get the technique approved.  -- They also used a truck monitor (array of ISOCS/Gamma Spec devices) to free release truck loads of soil.

If you are interested in more details, please contact RSCS:

Eric L. Darois, CHP
Executive Director
Radiation Safety and Control Services, Inc.
800 525-8339
603-778-2871 X29 (outside of USA)

The use of gamma spec detectors for open field applications predates ISOCS and was actually its forerunner.  Right after I got out of the Navy in '94, I sat in on a Canberra technical presentation/sales pitch by Frasier Bronson on sourceless calibration modelling for geometry correction for open field scans.  It inspired my Masters Thesis based on similar measurements that I performed on components in 3019 at ORNL in '95. 

They were conducting these open field measurements in the field at the time and were "in development" of the ISOCS application for other geometries (e.g., boxes, drums, etc.).  Bear in mind that they also had drum counters at that time, but those were calibrated with actual "blank" drums with sources distributed throughout them to simulate material distribution within the drum.  They came out with ISOCS [i.e., generic sourceless geometry correction calibration] a few years later.  Open field scans is its simplest and oldest application.

If you need more information on the history of the process or its technical details please contact me directly or go straight to the horse's mouth and contact Canberra [Their information may be more accurate but mine may sound like less of a sales pitch].

Hope this was helpful,


Answer 1. ISOCS does not replace scanning applications. Its designed for fixed point measurements.

Answer 2. Acceptance of the ISOCS technology depends on the regulatory agency you're dealing with. There's definitely some modeling voodoo that will need to be accepted by whomever has the responsibility for approving the data. I've found quite a few State Regulators unwilling to accept the ISOCS data alone in lieu of samples. My recommendation is to ask the question up front to whatever regulating agency you're dealing with.


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